My Jeep (Liberty 2002) with 113K miles. Had no problems in the past. Now there is. The car is dying when stops in traffic, unless put in neutral and then again in drive. Otherwise it starts vibrating and dies. You need to start it up again. The RPM is okay between 600-700.

Need more info... Have you noticed if the engine light comes on and then goes off or does it just stay off? Have you noticed any changes in rpms prior to shut off? Do you have isses with high idle periods when you start it up? If so, it sounds like a throtle body issue... Had a similar issue in my '88 xj, turns out it was the throtle body getting stuck in certain postions causing a high idle or causing it to shutter and die... Try cleaning it and the mass air flow sensor and that should take care of it... If not see your local shop for diagnosis...

This is totally random, and it is just a suggestion. I had the same problem last few weeks. 1997 jeep grand cherokee, 102,000 miles. I checked throttle body, idle air control (go through all that, very easy to clean and check) transmission, etc. It wasn't anything I could visualize and or troubleshoot. Took it to the shop today and they were airing on the side of electrical. All it took was the mechanic to knock the computer module and it stuttered, it was a connection issue or a broken pin. During start/stop and while driving off highway where the road has more bumps and such it would shake and cut out on me. We were going to replace it, but after taking it off to inspect (he couldn't check and re-soder, chrysler put a goo jell in there so you can't do anything with it) and replugging it back in, the jeep works fine. I'm just going to see how it performs over the next week as the computer modules are a few weeks out at the dealership and at least in the 1997 is a dealer only item.

Something to check out, its supposibly common in the mid 90s jeeps, and can present with a whole bunch of symptoms, I dont know about the KJ but it might be an idea.

Okay just cleaned the throttle body. Sprayed the whole cleanning can. Things better now. It doesn't die when stops or in traffic.
However, going around say 30 mph and tromp on the gas the jeep doesn't not down shift and accelerate? The RPMs go up to 5K but it just doesn't 'jump'. Did I screwed up some TPS switch or something else?

Okay just cleaned the throttle body. Sprayed the whole cleanning can. Things better now. It doesn't die when stops or in traffic. However, going around say 30 mph and tromp on the gas the jeep doesn't not down shift and accelerate? The RPMs go up to 5K but it just doesn't 'jump'. Did I screwed up some TPS switch or something else?

Quote:

Originally Posted by Tiras

Start stalling dying again on stops. It was better at some point, but maybe just a luck. What else could be wrong?

My opinion is the throttle body was dirty and needed cleaning anyway but that's not your root problem. I believe the tranny needs some maintenance, and quickly.

As a previous poster said, check the transmission fluid level after you've driven for about 30 minutes by putting on your emergency brake, shifting into neutral, and checking the fluid level. It should be at the Full line. If it isn't full, low fluid is what is causing the stalls at stops and also why the transmission isn't shifting down when you floor the accelerator. You said the engine is revving but the tranny isn't shifting down - that is a transmission problem. Think of it like your transmission is starved for fluid; without proper fluid levels the tranny can't do it's job.

If you haven't had a complete fluid flush and new filter now is the time to do it. I suggest you do so soon...

Just cleaned the IAC valve. So far so good. Question - that solenoid plunger stick. Does it have to go back and forth easily? Its very very hard to move. Anyways, I cleaned that stick and the mounting hole.
Need to drive more to see if helps.
Will report back later.

Once stopped the RPM struggling and finally stops. Starting engine back no problem. Also if I idle RPM to very high like 4-5 and release the padal the engine dies too. Doesn't hold low RPM after immediate high.